In general, a cutting tool for remove material from a metallic workpiece is used in a lathe or milling machine or a drilling machine, and is also referred as a bite of the lathe machine, a cutter of the milling machine, or a drill of the drilling machine, which are configured to remove material from a workpiece. In particular, an end mill used for the milling machine is a tool configured to cut a material from a workpiece in all directions, since the end mill has a cutting edge on a top surface and a side.
Since such a cutting tool is a sharp cutting edge which is sensitive to impact, the cutting tool or an operator can be damaged during distribution, and thus the cutting tool is kept in a storage case for the purpose of the distribution. The cutting tool should be easily kept in the case at packing. One example of the storage case for the cutting tool is disclosed in Korean Patent No. 930734, in which lower and upper cases for housing the cutting tool are integrally formed through injection molding to reduce manufacturing costs. The case includes the lower case and two opening members, and a lower end of each opening member is foldably connected to the lower case, and is provided with outward and inward protrusions.
The above case disclosed in the patent has some drawbacks in that since a shank of the tool is forcibly fitted into a standardized insertion portion of the lower case, the insertion portion is thermally deformed due to a temperature difference between night and day and seasons, in that since a dimensional deviation is not uniform depending upon variations in injection conditions, a holding degree is not constant, so that if a retaining force is strong, it is hard to put the cutting tool in or out away from the insertion portion, and in that when the cutting tool is pulled while holding the cutting edge, fingers may be cut. The insertion portion has a retaining force of about 1 kg so that the shank can be easily inserted into or retracted from the insertion portion. If the retaining force is weak, the shank of the cutting tool may be retracted from the insertion portion due to impact, for example, the case is dropped on a ground due to careless handling during distribution. In this instance, the cutting edge collides with the inside of the case, so that the cutting edge is damaged. Also, since the cutting tool moves in the case, the inside of the case is scratched, it has a bad appearance.
In the case of a conventional storage case including a bit housing and a shank housing, separately, since the shank is also pushed into the shank housing, it is hard to pack and unpack the cutting tool. In particular, since the storage case is configured to easily put the cutting tool in or out away therefrom, there is a limit of the retaining force. In the case where the storage case is dropped on the ground, the shank is extracted from the shank housing, and then collides with the inside of the storage case, so that the cutting edge is damaged, and the inside of the storage case is scratched, which deteriorates the merchantable quality thereof
In addition, in order to prevent the shank housing from easily releasing from the bit housing, outer corners of the shank housing are provided with a plurality of latch bosses, and inner corners of the bit housing are provided with a plurality of locking grooves, so that the bit housing is engaged to the shank housing by engagement of the latch bosses and the locking grooves. However, since the latch bosses are released from the locking grooves by strongly pulling the shank housing, it causes inconvenience in use, for example, the shank housing should be pulled out with strong force.